Stratum corneum proteins and extracellular matrix components

The stratum corneum (SC) is the outermost layer of the epidermis, serving as the primary physical and chemical barrier of the skin (Source: StatPearls, Physiology, Stratum Corneum). It consists of corneocytes—terminally differentiated keratinocytes—embedded in a lipid-rich extracellular matrix (Source: Journal of Investigative Dermatology, The Skin Barrier). Key proteins include filaggrin, which aggregates keratin filaments, and loricrin and involucrin, which form the cornified envelope (Source: UniProt, Filaggrin). The extracellular matrix is composed of ceramides, cholesterol, and free fatty acids organized into lamellar bilayers (Source: PubMed, Lipids and the Skin Barrier). Dysfunction in these proteins or the lipid matrix leads to impaired barrier function, characteristic of diseases like atopic dermatitis and psoriasis (Source: NIH, Atopic Dermatitis). Therapeutic interventions often aim to replenish these components or modulate their synthesis to restore skin integrity and hydration (Source: PubChem, Ceramides).

Other names

Skin barrier componentsEpidermal barrierCornified envelope proteinsIntercellular lipid matrixCorneocyte-lipid complex

Restoration of the skin barrier through hydration, replenishment of essential lipids, and modulation of corneocyte desquamation (Source: Journal of Clinical and Aesthetic Dermatology).